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Effect of carrion size on the succesion of the nephilous insect society
Mikátová, Šárka ; Šípek, Petr (advisor) ; Jakubec, Pavel (referee)
The aim of this work was to assess the effect of carrion size on insect communities succession based on previously published studies. Assessement of various factors on carrion is important in forensic analysis and to determine the PMI (post morte interval). The most abundant and investigate groups of carrion insects are Diptera and Coleoptera. Model organism in most cases is a pig (Sus scrofa L). Decomposition of small carrions varies from medium and large size carrion, which causes different succession of insects. Relevant judging of differences between studies is not possible because of many factors which affect carrion decomposition. Key words: necrobiont insects, carrion, body size, Diptera, Coleoptera
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Sexual selection in Scarab beetles with empahsis to the subfamily Scarabaeinae (Coleoptera: Scarabaeoidea)
Kněnická, Kateřina ; Šípek, Petr (advisor) ; Král, David (referee)
Sexual selection is a very important phenomenon in nature. In this work, I focused on the mechanisms of sexual selection in scarab beetles, with a strong emphasis on group Scarabaeinae (Coleoptera: Scarabaeoidea: Scarabaeinae). The first part is devoted to selection and its classification the sexual reproduction and related effects. I tried to describe the list of forms of sexual dimorphism in individual families and groups of Scarabaeoidea and describe life strategies subfamilies Scarabaeinae. Finally I list the factors influencing the individual the attractiveness in the relation to mating success. Powered by TCPDF (www.tcpdf.org)
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Beetles on carrion: life strategies and ecological classification
Kadlec, Jakub ; Šípek, Petr (advisor) ; Růžička, Jan (referee)
This work summarizes available information about beetle communities on carrions, their life strategy and ecology classification. Necrobiotic beetles are very important part of the decomposition process and the return of organic mass to the life cycle. We can classify decomposition by several criterions, most commonly by the overall appearance of the carrion and by the species of present insect. Conclusions are different depending on authors. Process of decomposition of carrion is affected by the readiness of access for different species of insect. Insect succession depends on many factors, some factors increase the process and others decrease it. The interrelationships between different colonizators of carrion are very important, this relationship is described by three models of classic success ecology. Necrobiotic insect has specific adaptations for the life on carrion. For this thesis, we have chosen 13 families, which are often discussed in publications. The rest of 190 necrobiotic genuses from 34 families is listed in this thesis with their characteristic ecology.
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Fylogeography and intraspecific variability of the cetoniid beetle Potosia Cuprea
Fuchsová, Aneta ; Šípek, Petr (advisor) ; Růžička, Jan (referee)
The presented thesis deals with the intraspecific variability of flower beetles species complex Potosia cuprea (Fabricius, 1795), which is a complex of taxa at the species and subspecies level. Flower beetles from species complex Potosia cuprea are among the most variable Palaearctic Cetoniinae at all. Taxa included in the complex produces chromatic range varieties which were, and still are, perceived differently by different authors. Taxa included in the analyses come primarily from western Palaearctic region, with the main emphasis on European species and subspecies. The aim of this work is the use of molecular genetics methods to verify the justification of their species or subspecies level. At all, there were obtained sequences for two mitochondrial genes (cytochrome b and cytochrome oxidase I) from 14 taxa species complex Potosia cuprea and three related species P. angustata (Germar, 1817), P. fieberi (Kraatz, 1931) and P. marginicollis (Ballion, 1870). Molecular analyzes based on COI dataset and concatenate of CytB and COI revealed the existence of a "European" clade P. cuprea, which includes subspecies: Potosia cuprea bourgini (Ruter, 1967), P. c. brancoi (Barraud, 1992), P. c. cuprea (Fabricius, 1775), P. c. metallica (Herbst, 1790) a P. c. obscura (Mikšić, 1954), to which also fit two...
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Growth and ontogeny of sexual size dimorphism in Cetoniinae (Coleoptera: Scarabaeidae)
Vendl, Tomáš ; Šípek, Petr (advisor) ; Saska, Pavel (referee)
6 Abstract Due to its effect on fitness and many biological processes is body size one of the most important attribute of organisms. Body size is positively correlated with fecundity in insects and other ectotherms. Growth, which determine body size, is therefore crucial feature of animals. Study of growth can elucidate some aspects of body size evolution. Unfortunatelly, many insects life-history studies do not consider its complexity, especially the existence of distinct larval instars. Inaccurate record of growth trajectory may result also in biased differences in growth between sexually dimorphic sexes. Aim of this thesis is to record growth trajectories of two flower beetle species (Coleoptera: Scarabaeidae: Cetoniinae). These growth trajectories enable to define proximate mechanisms of growth with regard to individual instars. Determination of developmental mechanisms of sexual size dimorphism is another goal of this study. The growth is clearly divided in three distinct periods. In each individual period (i.e. instar) is described by asymptotic curve. The instars are not independent on each other - the growth in following instar is influenced by growth in previous. There are no differences in growth characteristics between sexes. Sexual size dimorphism is caused by differences in growth rate between...
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Population structure of flower chafer Oxythyrea funesta (Poda, 1761) and phylogeny of the genus Oxythyrea Mulsant, 1842
Vondráček, Dominik ; Šípek, Petr (advisor) ; Bezděk, Aleš (referee)
Eleven species are distinguished in the genus Oxythyrea Mulsant, 1842 (Coleoptera: Scarabaeidae) nowadays. They are not divided into subspecies. Diversity of the genus is concentrated in the Mediterranean and Oxythyrea funesta (Poda, 1761) inhabit a wide area in the western Palearctic Region. It was observed in last decades, that O. funesta retreated from central Europe to south and then recolonized it back including new areas in northern regions. Master thesis is focused on resolving population structure of O. funesta and partial phylogeny of the genus Oxythyrea using molecular genetic methods. 145 individuals of O. funesta and 15 individuals of five other species of the genus Oxythyrea appear in analysis. We acquired sequences of mitochondrial genes cytochrome oxidase I (807 bp), cytochrome b (381 bp) and nuclear gene internal transcribed spacer 1 (946 bp) from these specimens. The results of phylogenetic analysis confirmed so far the only one existing interpretation of relationships within the genus Oxythyrea based on morphological data. We also confirmed complicated relationships between O. funesta and O. pantherina, which also appear in the historical development of their taxonomy. We detected different genetic lineage in Sicily, southern Italy and Tunisia using phylogenetic trees and haplotype...
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Nedospělá stádia pleurostiktních listorohých brouků (Coleoptera: Scarabaeidae: Pleurosticti):morfologie, biologie a jejich význam pro fylogenetické studie
Šípek, Petr ; Král, David (advisor) ; Bezděk, Aleš (referee) ; Ahrens, Dirk (referee)
Summary: The immature stages of holometabolous insects are traditionally less studied than the adults. Albeit this neglect could be explained by the still unsatisfactory knowledge of adults, it is clear, that we lose a considerable amount of information on bionomy, ecology and also phylogeny of insects due to this constant ignorance. The thesis focuses on the immature stages of the very popular and widely known group of Scarab beetles (Coleoptera: Scarabaeidae), more precisely on the "pleurostict" or phytophagous scarab beetle clade, e.g. on larvae of various chafers, rhinoceros beetles or flower beetles. The work consists of three papers already published in international journals, one manuscript prepared for submission and a general introductory chapter focusing on the problematic aspects of scarab beetles phylogeny and the study of the immature stages of scarabs. As mentioned above, the Scarab beetles represent a widely know group of insects. Despite being so popular, the group is everything else but well studied (probably with the exception of alpha-taxonomical level), which is best demonstrated by the absence of a broadly accepted phylogenetical hypothesis of the whole group. In the first two papers included into the thesis we focused on the phylogenetic relationships within the group Cetoniinae (with...
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Ontogeny of exaggerated structures in dung beetles (Coleoptera: Scarabaeinae)
Žídek, Radim ; Hanus, Robert (referee) ; Šípek, Petr (advisor)
E n g l i s h a b s t r a c t Horns of scarab beetles represent a secondary sexual characters present mostly in males, to whom they serve as weapons in combats over the acces to females. In many species, two discrete male forms occur, "horned" and "hornless", which employ different reproductive strategies. Adult body size and horn morphology are determined by nutritional conditions encountered by larvae during their development. Switching between developmental pathways is accomplished by circulating levels of juvenile hormone (JH) which reflect body size, and genetically determined threshold of sensitivity to it. When body size is larger then threshold, horn growth occur, whereas if it's not, a brief pulse of ecdysone reprogramme the development and hornless adult emerge. Reprogramming the development encompass modifications of the insulin receptor pathway as well as changes in exact domains of genes expression envolved in specifying the proximodistal axis of the developing horn. Development of horns is morphologically reminiscent that of other insect appendages, with which it shares the expression of genes wingless, decapentaplegic, Distal-less, dachshund, homothorax, aristaless and EGFR, parts of gene regulatory network ensuring origin of the outgrowth of the cuticle. Some of them are expressed through...
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